Patent application number | Description | Published |
20080285772 | ACOUSTIC LOCALIZATION OF A SPEAKER - A system locates a speaker in a room containing a loudspeaker and a microphone array. The loudspeaker transmits a sound that is partly reflected by a speaker. The microphone array detects the reflected sound and converts the sound into a microphone signal. A processor determines the speaker's direction relative to the microphone array, the speaker's distance from the microphone array, or both, based on the characteristics of the microphone signals. | 11-20-2008 |
20080298602 | SYSTEM FOR PROCESSING MICROPHONE SIGNALS TO PROVIDE AN OUTPUT SIGNAL WITH REDUCED INTERFERENCE - A system reduces noise or other external signals that may affect communication. A device converts sound from two or more microphones into an operational signal. Based on one or both signals, a beamformer generates an intermediate signal. Reflected or other undesired signals may be estimated or measured by an echo canceller. Interference may be measured or estimated by processing the echo-reduced signal or estimate by a blocking matrix. An interference canceller may reduce the interference that may modify or disrupt a signal based on the output of the blocking matrix and the intermediate signal. | 12-04-2008 |
20090063143 | SYSTEM FOR SPEECH SIGNAL ENHANCEMENT IN A NOISY ENVIRONMENT THROUGH CORRECTIVE ADJUSTMENT OF SPECTRAL NOISE POWER DENSITY ESTIMATIONS - A system estimates the spectral noise power density of an audio signal includes a spectral noise power density estimation unit, a correction term processor, and a combination processor. The spectral noise power density estimation unit may provide a first estimate of the spectral noise power density of the audio signal. The correction term processor may provide a time dependent correction term based, at least in part, on a spectral noise power density estimation error of the actual spectral noise power density. The correction term may be determined so that the spectral noise power density estimation error is reduced. The combination processor may combine the first estimate with the correction term to obtain a second estimate of the spectral noise power density that may be used for subsequent signal processing to enhance a desired signal component of the audio signal. | 03-05-2009 |
20090067642 | NOISE REDUCTION THROUGH SPATIAL SELECTIVITY AND FILTERING - A signal processor uses input devices to detect speech or aural signals. Through a programmable set of weights and/or time delays (or phasing) the output of the input devices may be processed to yield a combined signal. The noise contributions of some or each of the outputs of the input devices may be estimated by a circuit element or a controller that processes the outputs of the respective input devices to yield power densities. A short-term measure or estimate of the noise contribution of the respective outputs of the input devices may be obtained by processing the power densities of some or each of the outputs of the respective input devices. Based on the short-term measure or estimate, the noise contribution of the combined signal may be estimated to enhance the combined signal when processed further. An enhancement device or post-filter may reduce noise more effectively and yield robust speech based on the estimated noise contribution of the combined signal. | 03-12-2009 |
20120294118 | Acoustic Localization of a Speaker - A system locates a speaker in a room containing a loudspeaker and a microphone array. The loudspeaker transmits a sound that is partly reflected by a speaker. The microphone array detects the reflected sound and converts the sound into a microphone array, the speaker's distance from the microphone array, or both, based on the characteristics of the microphone signals. | 11-22-2012 |
20130024196 | SYSTEMS AND METHODS FOR USING A MOBILE DEVICE TO DELIVER SPEECH WITH SPEAKER IDENTIFICATION - Systems, methods, and apparatus for using at least one mobile device to receive a representation of at least one audio signal. In some embodiments, the at least one audio signal comprises speech of at least one of a plurality of first participants of a meeting, the plurality of first participants participating in the meeting from a first location, and the at least one audio signal may be audibly rendered to at least one second participant of the meeting at a second location different from the first location. In some embodiments, the at least one mobile device may further receive an indication of an identity of a leading speaker of the speech in the at least one audio signal, the leading speaker being identified from among the plurality of first participants, and may render the identity of the leading speaker to the at least one second participant. | 01-24-2013 |
20130136271 | Method for Determining a Noise Reference Signal for Noise Compensation and/or Noise Reduction - The invention provides a method for determining a noise reference signal for noise compensation and/or noise reduction. A first audio signal on a first signal path and a second audio signal on a second signal path are received. The first audio signal is filtered using a first adaptive filter to obtain a first filtered audio signal. The second audio signal is filtered using a second adaptive filter to obtain a second filtered audio signal. The first and the second filtered audio signal are combined to obtain the noise reference signal. The first and the second adaptive filter are adapted such as to minimize a wanted signal component in the noise reference signal. | 05-30-2013 |
20140095156 | Single Channel Suppression Of Impulsive Interferences In Noisy Speech Signals - Methods and apparatus for reducing impulsive interferences in a signal, without necessarily ascertaining a pitch frequency in the signal, detect onsets of the impulsive interferences by searching a spectrum of high-energy components for large temporal derivatives that are correlated along frequency and extend from a very low frequency up, possibly to about several kHz. The energies of the impulsive interferences are estimated, and these estimates are used to suppress the impulsive interferences. Optionally, techniques are employed to protect desired speech signals from being corrupted as a result of the suppression of the impulsive interferences. | 04-03-2014 |
20140105338 | LOW-DELAY FILTERING - A method of frequency-domain filtering is provided that includes a plurality of filters, the plurality of filters including at least one constrained filter(s) | 04-17-2014 |
20140153740 | BEAMFORMING PRE-PROCESSING FOR SPEAKER LOCALIZATION - Methods and apparatus to beamform a first plurality of microphone signals using at least one beamforming weight to obtain a first beamformed signal, beamform a second plurality of microphone signals using the at least one beamforming weight to obtain a second beamformed signal, and adjust the at least one beam forming weight so that the power density of at least one perturbation component present in the first or the second plurality of microphone signals is reduced. | 06-05-2014 |
20140247953 | SPEAKER LOCALIZATION - Methods and apparatus for determining phase shift information between the first and second microphone signals for a sound signal, and determining an angle of incidence of the sound in relation to the first and second positions of the first and second microphones from the phase shift information of a band-limited test signal received by the first and second microphones for a frequency range of interest. | 09-04-2014 |
20140307883 | METHOD FOR DETERMINING A SET OF FILTER COEFFICIENTS FOR AN ACOUSTIC ECHO COMPENSATOR - Methods and apparatus for beamforming and performing echo compensation for the beamformed signal with an echo canceller including calculating a set of filter coefficients as an estimate for a new steering direction without a complete adaptation of the echo canceller. | 10-16-2014 |
20140337016 | Speech Signal Enhancement Using Visual Information - Visual information is used to alter or set an operating parameter of an audio signal processor, other than a beamformer. A digital camera captures visual information about a scene that includes a human speaker and/or a listener. The visual information is analyzed to ascertain information about acoustics of a room. A distance between the speaker and a microphone may be estimated, and this distance estimate may be used to adjust an overall gain of the system. Distances among, and locations of, the speaker, the listener, the microphone, a loudspeaker and/or a sound-reflecting surface may be estimated. These estimates may be used to estimate reverberations within the room and adjust aggressiveness of an anti-reverberation filter, based on an estimated ratio of direct to indirect (reverberated) sound energy expected to reach the microphone. In addition, orientation of the speaker or the listener, relative to the microphone or the loudspeaker, can also be estimated, and this estimate may be used to adjust frequency-dependent filter weights to compensate for uneven frequency propagation of acoustic signals from a mouth, or to a human ear, about a human head. | 11-13-2014 |